This non-implication,
Form 0 \( \not \Rightarrow \)
Form 105,
whose code is 4, is constructed around a proven non-implication as follows:
Hypothesis | Statement |
---|---|
Form 15 | <p> \(KW(\infty,\infty)\) (KW), <strong>The Kinna-Wagner Selection Principle:</strong> For every set \(M\) there is a function \(f\) such that for all \(A\in M\), if \(|A|>1\) then \(\emptyset\neq f(A)\subsetneq A\). (See <a href="/form-classes/howard-rubin-81($n$)">Form 81(\(n\))</a>. </p> |
Conclusion | Statement |
---|---|
Form 105 | <p> There is a partially ordered set \((A,\le)\) such that for no set \(B\) is \((B,\le)\) (the ordering on \(B\) is the usual injective cardinal ordering) isomorphic to \((A,\le)\). </p> |
The conclusion Form 0 \( \not \Rightarrow \) Form 105 then follows.
Finally, the
List of models where hypothesis is true and the conclusion is false:
Name | Statement |
---|---|
\(\cal M11\) Forti/Honsell Model | Using a model of \(ZF + V = L\) for the ground model, the authors construct a generic extension, \(\cal M\), using Easton forcing which adds \(\kappa\) generic subsets to each regular cardinal \(\kappa\) |